Deformable Cross-Car Beam for Side Impact Protection

ABSTRACT

Systems and methods that facilitate vehicle passenger protection during side impact events and, more particularly, to systems and methods which increase the survival space between the vehicle side structure and a vehicle passenger located in the vehicle passenger compartment while maintaining reasonable vehicle structure deceleration levels. The systems and methods enable the seat structure assemblies to move inboard during side impact events by coupling the seat structure assemblies to a deformable cross bar or beam. The embodiments include a deformable cross-car beam that is deformable in one or more locations along its length using changes in geometry and/or changes in material to initiate controlled deformation under a cross-car load due to a side impact event.

CROSS-REFERENCE TO RELATED APPLICATION

This application is a continuation of application Ser. No. 12/732,033filed Mar. 25, 2010, which claims the benefit of provisional applicationSer. No. 61/163,375 filed Mar. 25, 2009, which is fully incorporatedherein.

FIELD

The present invention relates generally to side impact protectionsystems and methods for automobiles or other vehicles and, moreparticularly, to systems and methods utilizing a cross-car beamextending between side structures that is deformable to facilitatepassenger protection during vehicle side impact collisions.

BACKGROUND

The automotive industry has taken significant steps over the years toincrease vehicle safety and crash worthiness. A substantial focus ofthese efforts has been on the passenger compartment and improving itsintegrity during a crash. In more recent years, automotive manufacturershave concentrated on addressing the effect of a side impact collision onthe passenger compartment. Safety standards have also been adoptedrequiring automotive manufactures to implement a dynamic side impactprotection system or apparatus for maintaining the integrity of thevehicle passenger compartment in response to side impact collisions bylaterally interconnecting the sides of the vehicle. One implementationof such standard is described in U.S. Pat. No. 5,954,390 as including across-car beam extending laterally within the passenger compartmentbetween vertically extending side structures on opposing sides of thepassenger compartment. The intent of the cross-car beam in the '390patent is to increase the lateral strength of the vehicle.

However, even in systems designed to maintain the integrity of thevehicle passenger compartment in response to side impact collisions, aside impact event will cause intrusion of the vehicle's side structuretowards a passenger located in the passenger compartment whileaccelerating the passenger outboard towards the deforming structuretending to cause serious injuries to the passenger.

Therefore, systems and methods that facilitate an increased gap betweenthe vehicle structure and the passenger during a side impact event and,thus, providing an additional level of safety for the passenger, aredesirable.

SUMMARY

The various embodiments and examples provided herein are generallydirected to systems and methods that facilitate vehicle passengerprotection during side impact events and, more particularly, to systemsand methods which increase the survival space between the vehicle sidestructure and a vehicle passenger located in the vehicle passengercompartment while maintaining reasonable vehicle structure decelerationlevels. The systems and methods enable the seat structure assemblies tomove inboard during side impact events by coupling the seat structureassemblies to a deformable cross bar or beam. In one embodiment, adeformable cross bar assembly includes first and second co-extensiverigid side portions and a deformable co-extensive central portion or“crush-can” portion coupled between the side portions. The deformablecross bar assembly is joined to the vehicle side structures. Thedeformable center portion is designed to deform at axial cross carimpact forces or loads that are sustainable without deformation by theside portions.

In another embodiment, a deformable cross-car beam includes multipletunable deformation zones along its length using changes in surfacegeometry and/or changes in material to initiate controlled deformationunder a axial cross car impact force or load.

Other systems, methods, features and advantages of the invention will beor will become apparent to one with skill in the art upon examination ofthe following figures and detailed description.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a rear perspective view of a partial vehicle body structurewith a deformable cross-car beam system for side impact protection.

FIG. 1A is a perspective view of a deformable cross-car beam shown inFIG. 1.

FIG. 2 is another rear perspective view of the partial vehicle bodystructure with a deformable cross-car beam system shown in FIG. 1.

FIGS. 3 and 3A are perspective views of the deformable cross-car beamsystem and deformable cross-car beam shown in FIGS. 1 and 1A following aside impact event.

FIG. 4 provides before and after side impact event perspective views ofthe deformable cross-car beam system shown in FIG. 1.

FIGS. 5A through D show before and after side impact event plan views ofthe deformable cross-car beam tube shown in FIG. 1A.

FIGS. 6 and 6A are perspective views of the deformable cross-car beamsystem and deformable cross-car beam shown in FIGS. 1 and 1A followingan IIHS side impact event.

FIGS. 7 and 7A are perspective views of the deformable cross-car beamsystem and deformable cross-car beam shown in FIGS. 1 and 1A following aFMVSS214 dynamic side impact event.

FIGS. 8 and 8A are perspective views of the deformable cross-car beamsystem and deformable cross-car beam shown in FIGS. 1 and 1A followingan oblique pole side impact event.

FIG. 9 is a rear perspective view of another embodiment of a partialvehicle body structure with a deformable cross-car beam system for sideimpact protection.

FIG. 10 is a perspective view of a deformable cross-car beam shown inFIG. 9.

FIGS. 11A and 11B are plan views of cross-sectional profile shapes ofthe deformable cross-car beam shown in FIGS. 10 and 11.

FIGS. 12 and 13 are perspective views of the deformable cross-car beamsystem and deformable cross-car beam shown in FIGS. 9 and 10 following aside impact event.

DESCRIPTION

The various embodiments and examples provided herein are generallydirected to a deformable cross-car beam system for side impactprotection and more particularly to a system which increases thesurvival space between the vehicle side structure and a vehiclepassenger located in the vehicle passenger compartment while maintainingreasonable vehicle deceleration levels. Side impact events tend to causeintrusion of the vehicle's side structure towards a passenger located inthe passenger compartment while accelerating the passenger outboardtowards the deforming structure causing serious injuries to thepassenger. Therefore, decoupling the passenger's deceleration from theintruding structure will allow for an increased gap between the vehiclestructure and the passenger, providing an additional level of safety forthe passenger. The embodiments described herein accomplish thisdecoupling by attaching the rear of the seat structure assemblies to across-car beam that is deformable at one or more locations along itslength under an axial cross-car impact force or load.

Although there are other concepts employed in vehicles today to protectagainst side impact collisions (see, e.g., U.S. Pat. No. 5,954,390),conventional cross-car beams perform a different function in passengersafety. Conventional cross-car beams serve as reinforcing membersbetween opposing “B” pillars or side structures, increasing the axialstiffness of the vehicle. The function of the deformable cross-car beamsof the embodiments provided herein is completely different. The purposeof the deformable cross-car beams described herein is to increase thesurvival space between the vehicle side structure and the passengerwhile maintaining reasonable vehicle deceleration and intrusion levels.This is achieved by deforming the cross-car beam at one or morelocations along its length, allowing for the decoupling of thereinforcement feature from the motion of the occupant away from thedeforming side structure.

Turning in detail to the figures, a preferred embodiment of a deformablecross-car beam system including a deformable tube 30 assembly isillustrated in FIGS. 1, 1A and 2. FIGS. 1 and 2 provide a rearperspective view of a partial body structure 10 or partial BIW defininga passenger compartment 11. As depicted, the passenger compartment 11 isdefined by opposing vertical side structures or vehicle B-pillars 12 and13 extending from outer frame rails 15 a and 15 b of an under bodystructure coupled, a floor pan 14 coupled to and extending between outerframe rails 15 a and 15 b, opposing roof side rails 18 and 19 coupled toand extending from the B pillars 12 and 13, and a roof cross-bar 16coupled to the roof side rails 18 and 19 at the B-pillars 12 and 13 andextending there between. Left and right seat structure assemblies 20 and21 are positioned within the passenger compartment.

The deformable tube assembly 30, which as shown in more detail in FIG.1A, includes first and second co-extensive rigid side portions 32 and 36and a deformable co-extensive central portion 34 or “crush-can” portioncoupled between the side portions 32 and 36. The tube assembly 30 isjoined to the vehicle BIW 10 at two locations on the inner structures ofopposing B-pillars 12 and 13 using attachment flanges 35 and 33 and twopoints on the vehicle floor pan 14 using attachment brackets 38 and 37.The tube 30 is designed to provide B-pillar 12 and 13 attachment, rearseat structure assembly attachment at adjustment rails 22 and 23, and adeformable center portion 34 that deforms at axial cross car crashforces that are sustainable without deformation by the side portions 32and 36. As depicted in FIGS. 3 and 4, this pre-determined deformationallows for the seat 20 to move inboard in a direction M away from theintruding vehicle side structure 12 during a side impact crash event.This enables an increased gap (survival space) 11A within the passengercompartment between the intruding structure 12 and the passenger in theseat 20 within the passenger compartment 11. Attachment brackets 38 and37, which extend from the tube 30 to the vehicle's floor pan 14 aredesigned to allow axial cross car motion while restricting verticalmotion.

Referring to FIGS. 5A through D, the tube assembly 30 is illustrated inits intact, before impact configuration and its after impact, crushedconfiguration with the center portion 34 deformed from IIHS, FMVSS214dynamic, and oblique pole type side impact events. Turning to FIGS. 6through 8A, the vehicle body structure 10 and tube assembly 30 areillustrated following IIHS, FMVSS214 dynamic, and oblique pole type sideimpact events. The tube 30 is designed to absorb pressure from any typeof accident that exerts pressure from either side on the tube assembly30. After impact, each of FIGS. 5A through 8A shows compression of thecrush can 34 upon external pressure exerted from the left side of thevehicle body structure 10. If there was external pressure from the rightside of the vehicle body structure, the image would be mirrored. BothFIGS. 6 and 7 show external pressure from a 90 degree angle. FIG. 8shows external pressure at a lesser angle, e.g., as if the vehicle slidinto a telephone pole at an oblique angle.

The “after impact” angle of the side portions, in these instance theleft side portion 32, of the tube 30 is a consequence of the angle atwhich the vehicle absorbed pressure. The side bars 32 and 36 are notlimited to move in a certain way, just in response to compression of thecrush can 34. In a preferred embodiment, the crush can is preferablyapproximately 100 mm wide and can preferably withstand compression in arange of approximately 15-20%.

In a preferred embodiment, the crush can or collapsible center portion34 of the tube 30 assembly is formed from a material, such as steel,composite or the like, that is intended to crush under loadssubstantially lower than loads sustainable without deformation by theside portion tubes 32 and 36 extending from the B-pillars 12 and 13 tothe center portion 34 of the tube 30 assembly. For example, in apreferred embodiment, the center deformable portion 34 of the tube 30assembly is preferably formed from 24000 PSI steel and the side portiontubes 32 and 36 are preferably formed from high strength steel notintended to deform, e.g., die form 140 (140,000 PSI) to provide aconfiguration in which the center deformable portion 34 will crush underloads substantially lower that loads that are sustainable withoutdeformation by the side portion tubes 32 and 36 extending from theB-pillars 12 and 13 to the center portion 34 of the tube 30.

Turning to FIGS. 9 through 15, a deformable cross-car beam system sideimpact protection system in accordance with an alternative embodiment isshown. FIG. 9 provides a rear perspective view of a partial bodystructure 100 or partial BIW defining a passenger compartment 111. Asdepicted, the passenger compartment 111 is defined by opposing verticalside structures or vehicle B-pillars 112 and 113 extending verticallyfrom outer frame rails 115 a and 115 b of an under body structure, afloor pan 114 coupled to and extending between outer frame rails 115 aand 115 b, opposing roof side rails 118 and 119 coupled to and extendingforward from the B pillars 112 and 113, a first roof cross-bar 116coupled to the roof rails 118 and 119 at the B-pillars 112 and 113 andextending there between, and a second roof cross-bar 117 extendingbetween the roof rails 118 and 119 in spaced relation with the firstroof cross-bar 116. Left and right seat structure assemblies 120 and 121are positioned within the passenger compartment 111.

The deformable cross-car beam system includes a controllably deformablecross beam 130 extending between and coupling to the outer frame rails115 a and 115 b at the B-pillars 112 and 113. Left and right seat railconnectors 122, 123, 124 and 125 are used to couple the left and rightseat structure assemblies 120 and 121 to the deformable cross beam 130,which is shown in more detail in FIGS. 10, 11A and 11B.

The cross beam 130 includes an elongate body 132 having top and sidewalls 141 and 142 forming a C-shape cross-sectional profile 140 a or ahat shape cross-sectional profile 140 b with chamfered corners. Anelongate stiffening bead 131 in the form of a cavity or groove extendingaxially along the longitudinal axis of the body 132 is formed in the topwall 141. The cross beam 130 includes flanged ends 133 and 135 to attachto the outer frame rails 115 a and 115 b at the B-pillars 112 and 113.

The body 132 of the deformable cross beam 130 is designed to includemultiple tunable deformation zones along its length using changes insurface geometry and/or changes in material to initiate controlleddeformation under a load due to an impact to the side of the vehicle.The body 132 of the deformable cross beam 130 can be formed from asingle material through a sheet metal forming process or the like wherechanges in the surface geometry determine where and how the body 132 ofthe cross beam 130 will deform. The change or changes in geometry createareas of varying strength and properties by their unique and tunablestructural section properties. Examples of geometry that can beimplemented to manage the deformation include grooves (both stiffeningand controlled deformation initiators). In addition to varying sectionalproperties the deformable cross beam can be developed from multiplematerials that are joined prior to the part being formed or as a part ofthe vehicle assembly process. The changes in material along the beam 30determines where and how the body 132 of the cross beam 10 will deform.The body 132 of the deformable cross beam 130 is preferably designed todeform or buckle at the deformation zones in an accordion fashion. Wherethe body 132 of the deformable cross beam 130 includes two or moredeformable zones per side or longitudinal half of the body 132 along itslength, the deformation zones are preferably tunable to enablesequential deformation of the body 132.

Turning in detail to FIG. 10, the body 132 of the deformable beam 130includes a central region 138 used to attach vehicle electronics betweenthe seat assemblies 120 and 121, and first and second side sections 137and 139 extending outwardly from the central region 138. Seat assemblymounting points or locations include side mounting points 126 and 129located adjacent the flanged ends 133 and 135 and central mountingpoints 127 and 128 located adjacent the central region 138 of the body132. As shown, the body 132 includes first and second transverse beads134 and 136 in the form of a cavity, groove or other depression in thesurface of the body 132 that create first and second deformation zonesalong the body 132. Although shown as symmetrically disposed on eitherside of the mid-plane of the body 132 along its longitudinal axis andtransversing the longitudinal axis parallel to the mid-plane of the body132, the first and second transverse beads 134 and 136 can beasymmetrically disposed and oriented at any angle relative to themid-plane of the body 132 that accomplishes a desired deformation.However, the first and second transverse beads 134 and 136 arepreferably located inside of or closer to the longitudinal mid-plane ofthe body 132 than the central seat assembly mounting points 127 and 128.

As depicted in FIGS. 12 and 13, the configuration of the body 132 of thedeformable cross beam 132 described above causes the seat assembly 120to move inboard in the direction M within the passenger compartment 111away from the intruding vehicle side structure 112 during a side impactcrash event as the body 132 of the deformable cross beam 130 deforms orbuckles in the deformation zone created by the first transverse bead134. This enables an increased gap (survival space) 111A within thepassenger compartment 111 between the intruding structure 112 and thepassenger in the seat of seat assembly 120.

As depicted in FIGS. 12 and 13, the body 132 of the deformable crossbeam 130 is shown to have buckled or deformed in the deformation zonecreated by the first transverse bead 134 and at other areas along thelength of the left half 137 of the body 132. Preferably, the deformationzone created by the first transverse bead 134 is tuned to deform orbuckle first or before other deformable locations along the body 132 inresponse to a side impact.

If there was external pressure to the right side of the vehicle bodystructure due to a side impact, the image in FIG. 12 would be mirrored.

While the invention is susceptible to various modifications, andalternative forms, specific examples thereof have been shown in thedrawings and are herein described in detail. It should be understood,however, that the invention is not to be limited to the particular formsor methods disclosed, but to the contrary, the invention is to cover allmodifications, equivalents and alternatives falling within the spiritand scope of the appended claims.

1. A deformable cross-car beam for vehicle side impact protection, comprising an elongate body couplable at its first and second ends to side structures of a vehicle passenger compartment, and one or more deformable regions located along the length of the body, the one or more deformable regions being deformable under axial loads sustainable by other regions of the body without deformation.
 2. The beam of claim 1 wherein the one or more deformable regions comprise a change in geometry along the length of the body.
 3. The beam of claim 2 wherein the change in geometry comprises a bead oriented transverse to a longitudinal axis of the body.
 4. The beam of claim 3 wherein the bead comprises a groove.
 5. The beam of claim 1 wherein the body has a C shape profile.
 6. The beam of claim 1 wherein the body has a hat shape profile.
 7. The beam of claim 1 wherein the one or more deformable regions comprise first and second beads formed in the body on opposing sides of a longitudinal mid-plane of the body, wherein the first and second beads a positioned closer to the longitudinal mid-plane than seat assembly connection points along the length of the body.
 8. The beam of claim 1 wherein the body comprises first and second side portions couplable at a first end to vehicle side structures, and a center portion couplable to a second end of the first and second side portions and co-extensively extending between the first and second side portions, wherein the center portion is deformable under an axial load that is sustainable by the first and second side portions without deformation.
 9. The beam of claim 8 further comprising first and second flanges coupled to the first end of the first and second side portions and adapted to couple the beam to side structures of a vehicle.
 10. The beam of claim 1 further comprising first and second brackets adapted to couple the beam to a floor pan of a vehicle and restrict vertical motion of the beam relative to the floor pan.
 11. A vehicle comprising a body understructure including first and second side rails, first and second side structures extending upwardly from the understructure on opposing sides of the understructure, and a cross beam coupled to and extending between the first and second side structures, the cross beam includes a configuration to deform axially inwardly in response to a crash force applied to the first or second side structures.
 12. The vehicle of claim 11 wherein the cross beam includes a central crush zone.
 13. The vehicle of claim 11 wherein the cross beam includes first and second side portions and a central portion extending between the first and second side portions, wherein the central portion is deformable under an axial load that is sustainable by the first and second side portions without deformation.
 14. The vehicle of claim 13 further comprising first and second brackets coupled to the cross beam to a floor pan coupled to the side rails and adapted to restrict upward motion of the cross beam relative to the floor pan while allowing lateral motion of the cross beam.
 15. The vehicle of claim 11 wherein the cross beam includes an elongate body have one or more deformable regions being deformable under axial loads sustainable by other regions of the body without deformation.
 16. The vehicle of claim 15 wherein the one or more deformable regions comprise a change in geometry or material along the length of the body.
 17. The vehicle of claim 16 wherein the change in geometry comprises a bead oriented transverse to a longitudinal axis of the body. 